This invention relates to a portable telephone apparatus which can be used in combination with a data processing apparatus, such as a personal computer or the like.
A recent technical development has brought a personal computer which is relatively small and which will be called hereunder a mobile computer. Generally, the mobile computer is designed so that it is possible to carry out data communication through a public communication network known in the art. On carrying out the data communication, a datum is transmitted between the personal computer and the public communication network and is processed by the personal computer. As a result, a user of the mobile computer can receive various services known in the art.
In addition, the mobile computer comprises a card connecting portion for connecting a card-shaped device which is generally called an IC memory card or a PC card. When the card-shaped device is connected to the card connecting portion, it becomes possible to transmit the datum between the data processing apparatus and the card-shaped device.
In order to carry out the data communication, it is necessary to connect the mobile computer with the public communication network. Recently, a proposal is made of using a portable telephone apparatus for connecting the mobile computer to the public communication network. For example, such a proposal is disclosed in Japanese Patent Prepublication No. 341,043 of 1992 by Masayuki Shimizu. As will later be described in detail with reference to the drawing, the proposal uses an adapter unit which is connected between the mobile computer and the portable telephone apparatus and is for establishing electrical matching therebetween. This results in enabling reception of the various services through the public communication network during movement of the mobile computer.
However, the adapter unit must always be carried together with the portable telephone apparatus and the mobile computer. In addition, a battery for the adapter unit must be carried. Taking the above into consideration, a portability is extremely inferior.